This invention relates to apparatus for discharging material in granular form together with a cooling liquid from a collecting vessel through a closable valve in the bottom of the collecting vessel. More particularly, the present invention relates to such a collecting vessel adapted to quench hot-liquid material discharged from an overflow in a pressure vessel disposed above the collecting vessel. The present invention is particularly useful to granulate and discharge slag passed from a slag bath generator while operating at an elevated pressure above atmospheric pressure.
There are several known processes which are carried out at an elevated temperature but these processes are only efficient when the process proceeds under an elevated pressure so that the dimensions of the treatment chambers can be reduced to an acceptable size, particularly in regard to chambers involving large throughput capacities.
As a rule, the processes taking place within pressure vessels, e.g., a slag bath generator, are carried out on a continuous basis whereby there is a continuous discharge of hot-liquid material which is cooled into granular form. It is important to avoid the need to employ apparatus having large physical dimensions to form the pressurized treatment chamber and the vessel in which the hot-liquid material is granulated by cooling. The hot-liquid material is slag in the case of a slag bath generator. To avoid the need for employing apparatus having large dimensions, it is necessary to make provisions for frequent depressurized delivery of the granulate which accumulates in the vessel.
An untolerable amount of labor is required to manually withdraw the granulate from the vessel. Moreover, inspection and monitoring of the level of material within a pressure vessel are very difficult if not impossible.
The residue from gas generators operating under an elevated pressure has been removed by employing a collecting vessel located below the pressure chamber and through the use of a sluice vessel that is filled with water and closed from the collecting vessel by a pivotal closure and ball valve. The residue is transferred into a buffer vessel located downstream by means of pressurized water under gas pressure provided by the pressure vessel so that the residue is discharged from the buffer vessel. A device of this type for removing the residue from gas generators is awkward and requires expensive additional apparatus.